During the presidential campaign, some antiwar critics of former Secretary of State Hillary Clinton said that Trump would be a less hawkish president than Clinton. Trump naming Bolton as secretary of state would call the quality of that analysis into question.
It's hard to imagine anyone less temperamentally suited to be the nation's chief diplomat than Bolton, except maybe Donald Trump himself. Trump's respect for "strong leaders" threatens to get us into war with other strong leaders and Bolton is anti-Russian, contrary to his potential boss.